How Do I Seal My RV Sink?

 A common issue for RVs and campers of all ages and conditions, is having a sink that leaks. Sometimes a leak is simply something that will occur over time, or sometimes hitting a curb or running over railroad tracks can shape the camper enough to where something will crack or the seal will come un-sealed. In order to prevent further water damage and properly use your RV’s kitchen or bathroom sink, you will want to find a method of re-sealing the sink as soon as possible.

There are a few different ways that you can do this easily on your own, although the specific method will be different based on what sealant you choose to use. Some sealants will come in squeezable tubes or the same tubes as caulk. However, if you choose to use a type of putty (such as plumbers putty) there is a more hands-on process for applying the sealant.

Most plumber’s putty comes in a can, so you will need to grab some of the putty and roll it into a long rope (about 3/8″ in diameter). Once the “rope” is long enough to fit around the sink, or area that needs to be sealed, press the putty down in place.

You will then need to check to make sure that all the fittings are tightened and that the putty is properly sealing off the leakage area. Then remove any excess putty from your sink. Using your fingers is one of the best methods since you can help force the putty into tight areas and small spaces. However, some people will use different tools (such as a plastic butter knife) to help move the putty into the desired area.

Not only should you know how to apply sealant, but you should also be aware of the right areas to seal your sink. If you have a galley (also known as the kitchen) sink, this would be considered a single-walled sink.

In contrast, a double-walled sink will typically be the bathroom sink. A double-wall sink will have an overflow prevention path to the drain pipe. These double-walled sinks will require sealing, on both the top and the bottom, because of the multiple water paths to reach the drain pipe.

The putty or sealant that you choose to use, should be placed on the inside (or the top side) of a galley-style sink. You will need to place it in between the drain/stopper tube lip and the sink drain hole surface. 

If you attempt to stop all your leaks and only place putty on the bottom – you will have water seeping past the threads of the tube and the large tightening nut. No matter how tight you make the connection between the nut and the bottom surface of the sink, if you only add sealant on one side it will fix your leak problem. 

Using putty on the underside of the sink, as well as the top, is the best and most reasonable idea. However, because of how an RV will flex in different temps and environments, you have to be careful not to leave any gaps between your nuts and bolts and the putty.

Even the smallest of gaps can lead to almost immediate leaks. This is why it may be helpful to consult with someone who is a plumber, as they can give advice on how to seal the sink based on personal experience, or based on the specifics of your RV camper.

Continue reading to learn more about sealing your RV sink, the different kinds of putty and sealant, and what sealant would work best for your situation:

What Should I Use To Seal My RV’s Sink?

Before you can seal your RV sink, you will need to choose the sealant that will work best for your situation. Based on whether or not your sink’s seal simply wore off or if something is cracked – there may be a few different options for you. But overall, almost any sealant that is used for plumbing or securing fittings will be suitable.

Plumber’s putty is one of the most recommended sealant options for anyone who wants to seal anything in a bathroom or kitchen – because it is reputable and professionals use it daily. Check out these four different sealant and putty options to choose from when sealing your RV’s sink:

  • Plumber’s Putty. This is one of the most recommended putty options for anyone who wants to DIY seal their camper sink. This putty is super simple to use, can be found at most any hardware store, and doesn’t harden so you can remove it later or start over. Plumber’s putty is used by professionals from all over the country and has been known for years as an excellent sealant. Unless you can’t get your hands on this kind of putty, we highly recommend using a plumber’s putty.

  • Rubber Gasket. A rubber gasket is something everyone should have on their sinks in the first place, putty will typically just be used in addition to the gasket – since leaks are so easy to come by. If you find your sink leaking for no apparent reason, it’s likely because the gasket is in need of replacement. Rubber gaskets are also something that is easy to find in any hardware store, if not, fiber gaskets are also suitable for your sink. You could also replace your sink’s entire basket altogether, which would include new gaskets and fittings.

  • Non-Water Based Silicon Sealant. If neither of the above is an option for you, or you simply want to try something else, any non-water-based silicon sealant should work just fine. This could mean caulk (non-water-based) or anything else you can find at a local hardware store. Keep in mind that your sealant should be used in addition to the gasket, and not by itself. However, a silicon sealant will have to cure for at least 24 hours and isn’t as easy to clean up as Plumber’s Putty.

Check out these great products to help you properly seal your RV’s kitchen or bathroom sink:

Professional Grade Plumber’s Putty

This professional-grade plumber’s putty is perfect for your next repair or project within your RV! This putty is super easy to use, will last for a very long time, and can be reusable or molded as needed. Check out this great product that is perfect for all kinds of plumbing projects around the RV camper!

KONE 3-1/2 Inch Sink Gasket Seal Ring

This gasket is perfect for your kitchen or bathroom sink! This will fit all standard 3-1/2 Inch kitchen basket strainers. This washer is designed for use in the sink drains and use in the repair or replacement of sink strainers. These rings are made of high-quality rubber, and will be durable! Check out here!

STAR BRITE Waterproof Silicone Sealant

This amazing waterproof sealant bonds to fiberglass, wood, glass, metal and some plastics; and can be used above and below the waterline. This sealant provides a waterproof, airtight bond, but can be easily removed; ideal for mounting deck hardware. It also dries tack-free in less than one hour, and cures completely in 24 hours; custom colors are available.

We hope this article helped you determine what to do if your RV sink needs re-sealed? Sharing problems and solutions can make RV living so much easier. So if we didn’t include something that you have experienced, please leave a comment below to share with others. Until then, enjoy, be safe and have fun RVing!